Looking to fill those empty garden spots quickly? Fast-growing plants are the perfect solution for bare patches, new garden beds, or areas that need a quick refresh. These speedy growers can transform empty spaces into lush, vibrant gardens in just a few months.
By July, you'll have beautiful, established plants that make your garden look complete. The right fast-growing varieties can provide privacy, ground cover, vertical interest, or splashes of color exactly when you need them most.
Annual Sunflowers
Annual sunflowers grow incredibly quickly, often reaching their full height of 5-8 feet in just 3 months. These cheerful yellow-faced flowers follow the sun throughout the day and create dramatic height in any garden space. Their fast growth makes them perfect for creating temporary privacy screens or focal points.
Sunflowers are remarkably easy to grow directly from seed in spring. They thrive in full sun and average soil, making them suitable for most garden conditions. For a July display, plant seeds in April or May and watch them shoot upward at an impressive rate of several inches per week.
Cosmos
Cosmos flowers deliver quick results with their delicate, daisy-like blooms in shades of pink, white, and red. These annuals grow rapidly from seed and can reach heights of 2-4 feet by early summer. Their airy, wispy stems create movement in the garden while filling empty spaces with color.
Cosmos are perfect for adding quick color to newly established beds. They're drought-tolerant once established and attract beneficial pollinators to your garden. For continuous blooms until fall, sow seeds directly in the ground after the last frost and they'll be flowering abundantly by July.
Zinnias
Zinnias are fast-growing annuals that produce vibrant, long-lasting blooms in nearly every color imaginable. These reliable flowers grow quickly from seed to reach heights of 1-3 feet, depending on the variety. Their sturdy stems make them excellent cut flowers while also filling garden spaces with bright color.
Plant zinnia seeds directly in the garden after the last frost has passed. They prefer full sun and well-draining soil but aren't fussy about soil quality. By July, you'll have armloads of blooms that continue through the first frost, providing constant color and attracting butterflies all summer long.
Morning Glories
Morning glories are fast-growing annual vines that can climb 10-15 feet in a single season. Their heart-shaped leaves create a dense screen, while their trumpet-shaped flowers in blue, purple, pink, or white open each morning. These vigorous climbers are perfect for quickly covering fences, trellises, or unsightly views.
For best results, nick the hard seed coat and soak morning glory seeds overnight before planting. Direct sow after all danger of frost has passed. These vines grow so quickly you can almost watch them climb, often adding several inches of growth daily during warm weather.
Sweet Peas
Sweet peas grow rapidly into fragrant climbing vines that reach 6-8 feet tall. Their delicate, ruffled blooms come in a rainbow of colors and fill the air with their distinctive sweet scent. These cool-season annual climbers make excellent cut flowers while also covering vertical spaces quickly.
Plant sweet pea seeds directly in the garden in early spring for blooms by early summer. They prefer cooler temperatures, so they'll establish quickly in spring and provide flowers by July in most regions. Give them a trellis or support to climb, and they'll quickly transform an empty vertical space.
Nasturtiums
Nasturtiums grow quickly from seed to produce cascading or bushy plants with distinctive round leaves. Their edible flowers in shades of red, orange, and yellow add a peppery kick to salads while brightening up garden spaces. These versatile plants can trail from containers or spread as ground cover.
Direct sow nasturtium seeds after the last frost date. They prefer poor to average soil and will actually bloom more profusely without fertilizer. By July, nasturtiums will have filled empty spaces with their bright colors and continue flowering until frost cuts them back.
Marigolds
Marigolds are fast-growing annuals that quickly fill spaces with bright orange, yellow, and red blooms. These reliable plants grow from seed to flower in just 8 weeks, reaching heights of 6 inches to 3 feet depending on the variety. Their distinctive scent may also help repel certain garden pests.
Plant marigold seeds directly in the garden after the last frost date. They grow best in full sun and average soil. By July, they'll be in full bloom and continue flowering until fall, providing consistent color in beds, borders, and containers.
Bachelor's Buttons
Bachelor's buttons (cornflowers) grow quickly from seed to produce classic blue flowers, though varieties also come in pink, white, and purple. These annual flowers reach about 1-3 feet tall and spread 1-2 feet wide, filling garden spaces with their frilly blooms that resemble tiny carnations.
Direct sow bachelor's button seeds in early spring for summer blooms. They're not fussy about soil and actually prefer conditions on the poorer side. By July, these easy-growing flowers will be in full bloom, attracting beneficial insects and adding old-fashioned charm to your garden.
Calendula
Calendula (pot marigold) grows rapidly from seed to produce sunny yellow and orange daisy-like flowers. These cool-season annuals reach 1-2 feet tall and spread about a foot wide, filling garden spaces with cheerful blooms that have medicinal and culinary uses. Their edible petals can brighten up summer salads.
Direct sow calendula seeds in early spring for continuous blooms through summer. They prefer full sun but tolerate partial shade, especially in hot climates. By July, calendula will be providing a steady supply of flowers that continue until the first hard frost.
Sweet Alyssum
Sweet alyssum grows quickly to form a low carpet of tiny, fragrant flowers in white, purple, or pink. This annual ground cover reaches just 3-6 inches tall but spreads 6-9 inches wide, making it perfect for filling gaps between larger plants or softening the edges of beds and walkways.
Direct sow sweet alyssum seeds after the last frost or start them indoors a few weeks earlier. They perform best in full sun but appreciate afternoon shade in hot climates. By July, sweet alyssum creates a honey-scented carpet that attracts beneficial insects and continues blooming until frost.
Annual Phlox
Annual phlox (Phlox drummondii) grows rapidly from seed to create mounds of star-shaped flowers in shades of pink, red, purple, and white. These fast-growing annuals reach about 6-12 inches tall and spread 8-10 inches wide, filling garden spaces with color from early summer until frost.
Sow annual phlox seeds directly in the garden after the last frost date. They prefer full sun and well-draining soil. By July, annual phlox creates colorful drifts that work beautifully in borders, containers, and rock gardens while attracting butterflies and hummingbirds.
Cleome
Cleome (spider flower) grows quickly to produce tall, airy plants topped with unique spider-like blooms in pink, white, or purple. These dramatic annuals can reach 3-5 feet tall in a single season, making them excellent for filling large empty spaces or creating background plantings.
Direct sow cleome seeds after the last frost date or start them indoors 6-8 weeks earlier. They grow best in full sun and tolerate a wide range of soil conditions. By July, cleome creates architectural interest in the garden with its distinctive flowers that continue blooming until frost.
Nigella
Nigella (love-in-a-mist) grows quickly from seed to produce delicate blue, pink, or white flowers surrounded by feathery foliage. These charming annuals reach about 1-2 feet tall and spread about a foot wide, filling garden spaces with their unique blooms followed by decorative seed pods.
Direct sow nigella seeds in early spring for summer blooms. They prefer full sun but tolerate light shade and aren't fussy about soil. By July, nigella creates ethereal drifts of color that look especially beautiful in cottage gardens and continue providing interest even after flowering.
California Poppies
California poppies grow rapidly from seed to produce bright orange, yellow, or pink cup-shaped flowers above finely cut blue-green foliage. These drought-tolerant annuals reach about 12-18 inches tall and spread about a foot wide, filling sunny garden spaces with silky blooms that open in sunshine.
Direct sow California poppy seeds in early spring where you want them to grow. They prefer full sun and well-draining soil, thriving in poor, sandy conditions. By July, California poppies create drifts of color that continue blooming until heat slows them down, then often resume in fall.
Radishes
Radishes are among the fastest-growing vegetables, ready to harvest in just 3-4 weeks from seed. These cool-season root vegetables produce attractive leafy tops and crisp, colorful roots that come in red, white, purple, or multicolored varieties. They're perfect for filling temporary garden spaces or gaps between slower-growing plants.
Direct sow radish seeds in early spring and continue succession planting every two weeks. They prefer full sun and loose, fertile soil. By July, you can have harvested several crops of radishes and used the space for summer vegetables or flowers.
Lettuce
Lettuce grows quickly from seed to harvest in just 45-55 days, depending on the variety. These cool-season leafy greens come in countless shapes, sizes, and colors from lime green to deep burgundy. They're perfect for filling spring garden spaces while waiting for summer crops to mature.
Direct sow lettuce seeds in early spring and continue succession planting until temperatures warm. They prefer partial shade in warmer weather. By July, you can transition the space to heat-loving crops after enjoying multiple harvests of fresh salad greens.
Arugula
Arugula grows extremely quickly, ready to harvest as baby greens in just 21 days or mature leaves in 40 days. This peppery salad green produces attractive lobed leaves that add distinctive flavor to salads and other dishes. It's perfect for filling early-season garden spaces or gaps between longer-season crops.
Direct sow arugula seeds in early spring and continue succession planting every two weeks. It grows best in full sun during cool weather but appreciates afternoon shade as temperatures rise. By July, you can have enjoyed multiple harvests and transitioned the space to summer vegetables or flowers.
Bush Beans
Bush beans grow quickly from seed to harvest in just 50-60 days. These productive vegetables don't require staking and produce tender green, yellow, or purple pods over several weeks. They're perfect for filling garden spaces with both ornamental value and edible harvests.
Direct sow bush bean seeds after all danger of frost has passed and soil has warmed. They grow best in full sun and fertile, well-draining soil. By July, bush beans will be producing abundant harvests while adding nitrogen to the soil for future crops.
Cucumbers
Cucumbers grow rapidly from seed to harvest in 50-70 days. These vining vegetables produce abundant yields of crisp, refreshing fruits perfect for summer salads and pickling. They quickly fill vertical spaces when trained on supports or can sprawl to cover ground areas.
Direct sow cucumber seeds after all danger of frost has passed and soil has warmed. They thrive in full sun and rich, well-draining soil. By July, cucumber vines will be climbing supports or spreading across the ground while beginning to produce their first harvests.
Summer Squash
Summer squash grows incredibly quickly from seed to harvest in just 40-50 days. These productive vegetables include zucchini, yellow squash, and patty pan varieties that produce abundant yields over a long season. Their large leaves and architectural form quickly fill empty garden spaces.
Direct sow summer squash seeds after all danger of frost has passed and soil has warmed. They grow best in full sun and rich, well-draining soil. By July, summer squash plants will be in full production, providing daily harvests of tender fruits for summer meals.
Basil
Basil grows quickly from seed to become bushy plants reaching 1-2 feet tall. This aromatic herb produces bright green leaves with distinctive flavor perfect for summer cuisine. It fills garden spaces with both culinary value and attractive foliage that pairs beautifully with flowers or vegetables.
Direct sow basil seeds after all danger of frost has passed or start them indoors 4-6 weeks earlier. Basil thrives in full sun and rich, well-draining soil. By July, basil plants will be lush and ready for regular harvesting, which encourages more growth and prevents flowering.
Dill
Dill grows rapidly from seed to reach heights of 2-3 feet with delicate, feathery foliage. This aromatic herb produces flat yellow flower heads that attract beneficial insects while providing distinctive flavor for culinary uses. It's perfect for filling garden spaces with airy texture and pollinator value.
Direct sow dill seeds in early spring and continue succession planting every few weeks. It grows best in full sun and well-draining soil. By July, dill will be reaching its mature height and may be flowering, providing both herbs for the kitchen and habitat for beneficial insects.
Transforming Your Garden Quickly
Fast-growing plants offer the perfect solution for gardeners who want to see results quickly. By selecting a mix of these speedy growers, you can transform empty spaces into vibrant, productive gardens by midsummer. The key is matching the right plants to your specific conditions and desired timeline.
Remember that even the fastest-growing plants need proper care to reach their full potential. Provide adequate water during establishment, especially during dry spells, and prepare soil properly before planting. With minimal effort and these rapid growers, your garden will be bursting with life and color by July.